Hmmm, go back to the basic's. If it has spark and fuel(i think you're having a spark issue) do a compression test. When you checked for spark did you check at each plug? I'm sure techline asked you if you checked pin fits, did you? What did the HDS give you for a ign. signal? BTW, you have a TL right? It sayes RL in your post but I know they never had a 2.5l .